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Old 09-21-2012, 08:00 PM
Dale
 
Default Kernel options and udisk

Michael Mol wrote:
> On Fri, Sep 21, 2012 at 3:15 PM, Dale <rdalek1967@gmail.com> wrote:
>> Volker Armin Hemmann wrote:
>>> Am Mittwoch, 19. September 2012, 16:18:34 schrieb Dale:
>>>> Volker Armin Hemmann wrote:
>>>>> Am Mittwoch, 19. September 2012, 01:51:49 schrieb Dale:
>>>>>> Raffaele BELARDI wrote:
>>>>>>> On 09/18/2012 11:03 PM, Dale wrote:
>>>>>>> And every day I hear about them finding more oil and gas that they
>>>>>>> didn't know was there before.
>>>>> I am sure everybody would love to hear about those findings. Especially
>>>>> the
>>>>> CEO's of BP, Shell etc.
>>>> Actually, the former CEO of Shell was on Fox Business not long ago
>>>> talking about some HUGE finds. He said that we, the USA, are sitting on
>>>> some of the largest oil fields. Here is one article I found but not
>>>> sure this is the same one the Shell guy was talking about since this
>>>> article is a few months old.
>>>>
>>>> http://www.usatoday.com/money/industries/energy/story/2012-05-15/1A-COV-ENER
>>>> GY-INDEPENDENCE/54977254/1
>>>>
>>>> Quoting from that:
>>>>
>>>> "It's no pipe dream. The U.S. is already the world's fastest-growing oil
>>>> and natural gas producer. Counting the output from Canada and Mexico,
>>>> North America
>>>> <http://content.usatoday.com/topics/topic/Places,+Geography/Regions/North+Am
>>>> erica> is "the new Middle East," Citigroup analysts declare in a recent
>>>> report."
>>>>
>>>> Note it said fastest growing producer. You have to find it and be able
>>>> to get it up before you can produce it. Yea, one day we will run out
>>>> but that's a good long ways off. We could get hit by some asteroid or
>>>> something that just completely destroys the planet and everything on it,
>>>> including all that oil and gas that people want to save up on.
>>>>
>>>> Have you heard about the new wells being drilled in North Dakota by any
>>>> chance? They are drilling for oil like crazy up there. That is just
>>>> one that I recall seeing on the news a good bit recently. There are
>>>> plenty of other finds.
>>> I also heard about gas in drinking water thanks to fracking. Do oil companies
>>> drilling in deep water because it is cheap, save and fun? Or do they want to
>>> go and drill in the Arktis because it is so lovely there? Hardly. There is a
>>> difference between 'something is there' and 'the prize and risk are worth it'.
>>> Do you remember that Gulf incident? BP surely hopes not. You should get used
>>> to it.
>>>
>>> and here:
>>> http://oilsandstruth.org/world-running-out-oil-says-exceo
>>>
>> I also remember the people that died trying to go to the moon but we did
>> it anyway. I have heard a lot of people talking about fracking and all
>> sort of myths about it. I have not seen proof that is in drinking
>> water. Even so, I have a well that we drove here and we drank off it
>> for years. It has a HUGE iron count and turns white clothes orange.
>> There is always something in water. It's just what water does. That is
>> why it gets filtered before it is used for drinking. By the way,
>> fracking has been around for something like 60 years. Not all the oil
>> that has been found recently requires fracking either. So, don't just
>> point to fracking and then claim that all oil is bad.
>>
>> The website you linked to is against oil from my google search. It
>> would be like quoting Al Gore for global warming, climate change or
>> whatever they call it this week.
>>
>>>>> Fact is, we are running out. The stuff that is found is either very hard
>>>>> to get - or not very much. Oh, and very little to start with. Consider
>>>>> current consumption.
>>>> Fact is, the same could be said for the Sun too. Science already says
>>>> it will run out of fuel one day.
>>> And now you went full stupid. There is a difference between 'a couple of
>>> decades' and '4 billion years'. But thanks for posting. That said a lot about
>>> you. I don't even care about the rest of your posting. This is plonk worthy
>>> stupid. So I stop right there, I don't want to get any of that.
>>>
>> Care to explain away that we could get hit my some asteroid too?
>> Yellowstone could erupt again and kill us all. Better get your "I'm
>> scared of everything" hat on.
>>
>> Who knows it is a couple decades? That was the thinking years ago
>> BEFORE finding all the new reserves of gas and oil.
>>
>> Careful calling someone stupid. It could come back and name calling on
>> the list is not a good thing. You should know better.
>
> Guys, this fell into politics, one of those categories of things you
> don't discuss in polite company. Not that I'm accusing anyone of being
> polite, it's just that these aren't issues that can generally be
> resolved, and it's certainly not something that comes anywhere close
> to being on-topic here.
>
> Now, could we go back to discussing software, packages, electronics
> and amplifiers? I found that portion of the thread utterly
> fascinating...
>

Kewl. I have built amps from scratch but not sure I would right now. I
haven't touched a transistor in a good long while. Heck, I had to
search for the class of amps to make sure I was speaking with some
degree of certainty. I have built a couple amps that were tube types.
I can certainly tell a difference between tube and transistors but can't
describe it. I just don't like all that heat, high voltages and such.
Plus, tubes ain't very cheap and have shorter lives, especially the
outputs.

Still wonder why those PWM amps never made it tho. They sound great and
waste about nothing.

Dale

:-) :-)

--
I am only responsible for what I said ... Not for what you understood or how you interpreted my words!
 
Old 09-21-2012, 09:15 PM
Alan McKinnon
 
Default Kernel options and udisk

On Fri, 21 Sep 2012 15:52:17 -0400
Michael Mol <mikemol@gmail.com> wrote:

> On Fri, Sep 21, 2012 at 3:45 PM, Alan McKinnon
> <alan.mckinnon@gmail.com> wrote:
> > On Fri, 21 Sep 2012 15:25:49 -0400
> > Michael Mol <mikemol@gmail.com> wrote:
> >
> >> Guys, this fell into politics, one of those categories of things
> >> you don't discuss in polite company. Not that I'm accusing anyone
> >> of being polite,
> >
> > Phew, glad to hear that last bit. You had me worried for a second,
> > what with my reputation to uphold and all
> >
> >
> >> Now, could we go back to discussing software, packages, electronics
> >> and amplifiers? I found that portion of the thread utterly
> >> fascinating...
> >
> > That's a good idea. Would you like to hear about Hitachi Class H
> > amps?
> >
> > I'm forever fascinated that I seem to be the only person that ever
> > heard of them. Most techies know A, AB and B. Some know Class C but
> > I get blank looks everywhere I mention Class H...
>
> I would indeed. And a primer (or reasonable reference for someone with
> just a technician's amateur radio license) on class C.
>

IIRC this was back in the late 70s or early 80s. Someone at Hitachi
figured that amps (like code) spent 90% of their time doing 10% of the
effort. If you had a 100W amp, it wasn't trying to drive 100W into the
speakers all the time - only when the input signal was large enough.

And yet, the power source for the output stages was permanently running
at 70V or so (that's what it takes to get 100W into speaker coils back
then). A transistor isn't a perfect isolator when biased off, so some
of that voltage gets dropped somewhere (across the output transistors)
and the result is a lot of wastage.

wikipedia has a quite good summary of the usual classes - A, B, AB, C &
D:

http://en.wikipedia.org/wiki/Electronic_amplifier#Class_C

But, Class H. A Hitachi engineer had a brilliant idea:

Run the damn thing class A all the time (for the audio quality) but at
around 24V. Heat generated is minimal. The power supply had a fancy
voltage tripler circuit and when the input warranted it, the supply
voltage would (very rapidly) switch over to the full 70V and the amp
would deliver the full rated output. There was fancy circuitry in place
to avoid distortion at the switch on point of course, but that is a bit
OT.

An interesting take on the problem. Mechanical engineers do this all
the time with engines - turbos only kick in when you need the power
boost they provide, the rest of the time the motor is in regular mode.

I've promised myself for years since my apprentice days that I would
one day built a valve amp from a kit. There's something about the warm
glow from the tubes on a winter night that is appealing :-) I'd better
hurry up and get on with it, I read that decent quality valves are
becoming scarce and are generally only available from (what used to be)
the USSR.




--
Alan McKinnon
alan.mckinnon@gmail.com
 
Old 09-22-2012, 04:04 AM
Samuel Ports
 
Default Kernel options and udisk

Modern version
http://www.babeland.com/hitachi-magic-wand/d/2487

Sent from my iPhone

On Sep 21, 2012, at 5:18 PM, Alan McKinnon <alan.mckinnon@gmail.com> wrote:

> On Fri, 21 Sep 2012 15:52:17 -0400
> Michael Mol <mikemol@gmail.com> wrote:
>
>> On Fri, Sep 21, 2012 at 3:45 PM, Alan McKinnon
>> <alan.mckinnon@gmail.com> wrote:
>>> On Fri, 21 Sep 2012 15:25:49 -0400
>>> Michael Mol <mikemol@gmail.com> wrote:
>>>
>>>> Guys, this fell into politics, one of those categories of things
>>>> you don't discuss in polite company. Not that I'm accusing anyone
>>>> of being polite,
>>>
>>> Phew, glad to hear that last bit. You had me worried for a second,
>>> what with my reputation to uphold and all
>>>
>>>
>>>> Now, could we go back to discussing software, packages, electronics
>>>> and amplifiers? I found that portion of the thread utterly
>>>> fascinating...
>>>
>>> That's a good idea. Would you like to hear about Hitachi Class H
>>> amps?
>>>
>>> I'm forever fascinated that I seem to be the only person that ever
>>> heard of them. Most techies know A, AB and B. Some know Class C but
>>> I get blank looks everywhere I mention Class H...
>>
>> I would indeed. And a primer (or reasonable reference for someone with
>> just a technician's amateur radio license) on class C.
>>
>
> IIRC this was back in the late 70s or early 80s. Someone at Hitachi
> figured that amps (like code) spent 90% of their time doing 10% of the
> effort. If you had a 100W amp, it wasn't trying to drive 100W into the
> speakers all the time - only when the input signal was large enough.
>
> And yet, the power source for the output stages was permanently running
> at 70V or so (that's what it takes to get 100W into speaker coils back
> then). A transistor isn't a perfect isolator when biased off, so some
> of that voltage gets dropped somewhere (across the output transistors)
> and the result is a lot of wastage.
>
> wikipedia has a quite good summary of the usual classes - A, B, AB, C &
> D:
>
> http://en.wikipedia.org/wiki/Electronic_amplifier#Class_C
>
> But, Class H. A Hitachi engineer had a brilliant idea:
>
> Run the damn thing class A all the time (for the audio quality) but at
> around 24V. Heat generated is minimal. The power supply had a fancy
> voltage tripler circuit and when the input warranted it, the supply
> voltage would (very rapidly) switch over to the full 70V and the amp
> would deliver the full rated output. There was fancy circuitry in place
> to avoid distortion at the switch on point of course, but that is a bit
> OT.
>
> An interesting take on the problem. Mechanical engineers do this all
> the time with engines - turbos only kick in when you need the power
> boost they provide, the rest of the time the motor is in regular mode.
>
> I've promised myself for years since my apprentice days that I would
> one day built a valve amp from a kit. There's something about the warm
> glow from the tubes on a winter night that is appealing :-) I'd better
> hurry up and get on with it, I read that decent quality valves are
> becoming scarce and are generally only available from (what used to be)
> the USSR.
>
>
>
>
> --
> Alan McKinnon
> alan.mckinnon@gmail.com
>
>
 
Old 10-06-2012, 10:19 PM
Dale
 
Default Kernel options and udisk

Alan McKinnon wrote:
> I've promised myself for years since my apprentice days that I would
> one day built a valve amp from a kit. There's something about the warm
> glow from the tubes on a winter night that is appealing :-) I'd better
> hurry up and get on with it, I read that decent quality valves are
> becoming scarce and are generally only available from (what used to
> be) the USSR.

Found a few sites for ya:

http://tctubes.com/about-us.aspx

http://electrontubestore.com/index.php?main_page=contact_us

http://www.tubesandmore.com/customer_service/about_us

I found that by typing 6gh8a in google. That's a old tube that I used
to have to replace pretty regular. I think it was used in the audio
section and would usually work fine when cold but get a bit weird when
it gets good and hot. They got replaced a LOT back then. Anyway, two
are in the USA but one is in Canada.

Maybe you got more time than you think. ;-) I do think the old tubes
have better sound tho. I can't explain it but they just sound
different. I think that is why some places still have tubes. Some
people just like them more. I think they make great heaters. lol

Dale

:-) :-)

--
I am only responsible for what I said ... Not for what you understood or how you interpreted my words!
 
Old 10-07-2012, 02:42 AM
Adam Carter
 
Default Kernel options and udisk

> I'd better
> hurry up and get on with it, I read that decent quality valves are
> becoming scarce and are generally only available from (what used to be)
> the USSR.

There's a huge market for valves for guitar amps. I think supply is safe enough.
 
Old 10-07-2012, 12:13 PM
Alan McKinnon
 
Default Kernel options and udisk

On Sat, 06 Oct 2012 17:19:57 -0500
Dale <rdalek1967@gmail.com> wrote:

> Alan McKinnon wrote:
> > I've promised myself for years since my apprentice days that I would
> > one day built a valve amp from a kit. There's something about the
> > warm glow from the tubes on a winter night that is appealing :-)
> > I'd better hurry up and get on with it, I read that decent quality
> > valves are becoming scarce and are generally only available from
> > (what used to be) the USSR.
>
> Found a few sites for ya:
>
> http://tctubes.com/about-us.aspx
>
> http://electrontubestore.com/index.php?main_page=contact_us
>
> http://www.tubesandmore.com/customer_service/about_us
>
> I found that by typing 6gh8a in google. That's a old tube that I used
> to have to replace pretty regular. I think it was used in the audio
> section and would usually work fine when cold but get a bit weird when
> it gets good and hot. They got replaced a LOT back then. Anyway, two
> are in the USA but one is in Canada.

Cool finds, thanks!

Maybe I should go-ahead and build an amp and be done with it. No more
mucking about putting it off :-)

> Maybe you got more time than you think. ;-) I do think the old tubes
> have better sound tho. I can't explain it but they just sound
> different.

You're not imagining things. Valves do sound better and you can measure
it and see why.

Valves and transistors both distort sound to some degree as all
electronic systems will. The difference is in how the distortion
happens.

Semiconductors are prone to even-harmonic distortion, so if you have a
100Hz sine wave, it will produce distortion at 100hz, 400Hz, 1600Hz and
so on. Valves produce odd-harmonic distortion, at 200Hz, 800Hz and so
on.

If you are now thinking "Fourier" and wondering if transistors try to
make square waves, you are bang on the money because that is exactly
what is happening. To the human ear, a square wave sounds like gross
horrendous distortion, even at very small percentages. At it's worst,
this is "clipping" and happens because a transistor will happily pass
current until the voltage drop over it hits the supply voltage and it
clips. Bingo, one square(ish) wave and horrible sound.

Valves deal with this in a more "analog" fashion, as the voltage drop
nears the supply voltage it passes less and less current, rounding the
waveform and never actually clipping it. Which sounds far more pleasant
to the human ear.

Modern circuitry tries to avoid the transistor problem using "soft
clipping" and other tricks - basically trying to make the transistor
behave in the same way a valve oes. This does make a huge difference,
but you can never completely eliminate the device's inherent
characteristics, it is what it is and this leopard doesn't change it's
spots.



> I think that is why some places still have tubes. Some
> people just like them more. I think they make great heaters. lol
>
> Dale
>
> :-) :-)
>



--
Alan McKinnon
alan.mckinnon@gmail.com
 

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